Realize four kinds of common sine wave, triangle, sawtooth, square wave (A, B) t...

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实现4种常见波形正弦、三角、锯齿、方波（A、B）的频率、幅度可控输出（方波 A的占空比也是可控的），可以存储任意波形特征数据并能重现该波形，还可完成 各种波形的线形叠加输出。 -Realize four kinds of common sine wave, triangle, sawtooth, square wave (A, B) the frequency, magnitude controllable output (square wave A, is also a controllable duty cycle), can store arbitrary waveform feature data and can reproduce the waveform, but also completed a variety of linear superposition of the output waveform.